Abstract: A fail-safe gas valve driver circuit controlling the gas supply line of a gas burner, which circuit in its essential circuit elements (FIG. 1) includes an appropriate switching means (S1) effectively feeding a pulsed DC wave form into the rest of the valve relay driver circuit, operatively consisting only of a capacitor (C1) in series with a gas valve relay (K1), which in turn is in parallel with a diode (D1). In operation, the valve relay coil is energized by charging the capacitor with the switch connected to a positive DC voltage source (V.sub.dc ; FIG. 1A), and then grounding the positive end of the capacitor (switch connected to ground) applying a negative voltage across the coil of the relay (FIG. 1B). When the capacitor is again connected to the positive DC voltage source by the switch, the current in the relay coil is sustained by the diode (FIG. 1C).

Abstract: A method of hermetically sealing an electrical feedthrough (5) in a semiconductor-on-insulator device comprising the steps of producing an electrically insulating layer (2) on a semiconductive material (1) having a first surface area, producing one or more electrodes (4) on a non-conductive substrate (3) of a second surface area which may be greater than the first surface area, with each electrode having an electrical feedthrough (5) associated therewith, placing the semiconductive layer on the substrate with the insulating layer in contact with the substrate and such that each electrical feedthrough extends beyond the edge of the semiconductive layer, and bonding the semiconductive layer to the substrate to provide an hermetic seal around the feedthrough and thus protect the integrity of the electrode associated therewith and disposed between the semiconductive layer and the substrate.

Abstract: A rotary digital contacting encoder (FIG. 1) including a base (5), comprising - a base epoxy disk (501) with three external, pre-molded in place, connector pins (P.sub.1 -P.sub.3) on its exterior side extending through it, and a conductive layer in the form of two concentric layer rings (502 & 503; FIG. 4); and - an encoder element made of a "Kapton" insulating substrate (510) carrying two, like concentric cog rings (511B & 511A; FIGS. 3 & 7) on its top side. Conductive vias (512 & 513) electrically interconnect each respective cog ring with its respective conductive layer ring and its respective external connector pin, the vias forming conductive paths through the insulating substrate between the conductive layer and the cog rings. The presence of the conductive layer 502/503, which can be screen printed on the base disk, greatly simplifies the relative alignment of the encoder element, conductor pads and terminals.

Abstract: A rotary digital contacting encoder (FIG. 1) including a base (5), comprising--a base epoxy disk (501) with three external, pre-molded in place, connector pins (P.sub.1 -P.sub.3) on its exterior side extending through it, and a conductive layer in the form of two concentric layer rings (502 & 503; FIG. 4); and--an encoder element made of a "Kapton" insulating substrate (510) carrying two, like concentric cog rings (511A & 511B; FIGS. 3 & 7) on its top side. Conductive vias (512 & 513) electrically interconnect each respective cog ring with its respective conductive layer ring and its respective external connector pin, the vias forming conductive paths through the insulating substrate between the conductive layer and the cog rings. The presence of the conductive layer 502/503, which can be screen printed on the base disk, greatly simplifies the relative alignment of the encoder element, conductor pads and terminals.

Abstract: A control system for a microwave oven includes a magnetron power circuit, an electronic controller, and input control circuitry. The control system is adapted to be connected to a source of electrical power, typically an AC line supply. The line supply may be converted to DC for powering the electronic controller, however, the input control circuitry is structured to prevent connection of the power supply to the electronic controller until an intentional manual action occurs. This prevents the electronic controller from responding to noise or the like to become unintentionally powered and thus possibly operate in an undesired state. The input control circuitry includes switches associated with data input keys for temporarily connecting power to the controller when actuated. Such actuation of a data key enables the system to be powered-up and also to enter data.

Abstract: An integrated electronic control arrangement is disclosed in the illustrative environment of burner such as in a gas-fired furnace. The control incorporates a self-test feature which shuts down the furnace in the event of any one of a number of possible sensed faults. Self-testing occurs automatically before an attempt at ignition and during furnace operation. Proper functioning of the sensor which senses for induced air flow through the burner combustion chamber is tested prior to enabling a fan which causes that induced air flow. Air flow is confirmed by sending to and receiving back from the sensor a sequence of pulses. Should air flow not be sensed during a combustion period, combustion is terminated. A flame sensor is provided for determining the presence of a flame in the combustion chamber. During times when a flame should be present, pulse sequences are sent to and received back from the flame sensor to confirm that a flame is present.

Abstract: A speed detector, for use with a tone wheel having metal teeth, employs two coils positioned in offset relation near the tone wheel for interacting with the tone wheel teeth and thus changing their respective inductances. The coils preferably include iron cores to enhance magnetic coupling. One coil is in a phase sense oscillator circuit and the other is an a tuned sensor network. The oscillator is coupled to, and drives, the tuned network. The change in coil inductances effects a phase shift of the resulting signals in the oscillator and the tuned network, the magnitude of that phase shift typically being double that for a comparable single coil system. The output signals of the oscillator and tuned network provide inputs to a phase condition detector which looks for a reversal in their phase sequence and uses such event to provide timing reference pulses for a final determination of speed in a known manner.

Abstract: A sensor is connectable with a load circuit via two conductors. The sensor receives its electrical power from the load circuit via the two conductors and similarly provides its output signal indicative of the sensed phenomenon via the same conductors. An unregulated source potential is provided to a terminal of the sensor from a supply potential via the load circuit. Voltage regulating circuitry in the sensor converts the unregulated source potential to a regulated operating potential for its active circuit elements. Certain output circuitry in the sensor is connected to the terminal having the unregulated source potential for conveying an output signal from the sensor to the load circuit.

Abstract: An integrated electroluminescent display (DCEL), in which the DCEL (11) is integrated into the substrate board (10), such as, for example, a printed circuit board, which carries associated electronic components (12), such as, for example, those which would make up a control circuit, the DCEL displaying pertinent information for the control circuit. The bottom electrode (13) for the DCEL can be copper foil, which is etched at the same time as the rest of the foil pattern (13A) used to electrically interconnect the control components (12) of the overall control circuit during the making of the printed circuit board. Thereafter, the phosphor layer (14) is printed onto the associated copper foil segments, and, finally, a glass (15), which has on its inner surface an appropriate pattern of tin oxide (16), is placed on top of the phosphor depositions.

Abstract: A speed detector, for use with a tone wheel having metal teeth, employs two coils positioned in offset relation near the tone wheel for interacting with the tone wheel teeth and thus changing their respective inductances. One coil is in a phase sense oscillator circuit and the other is in a tuned sensor network. The oscillator is coupled to, and drives, the tuned network. The change in coil inductances effects a shifting of the phase of the output signal from the oscillator relative to the output signal from the tuned network. The phase sequence of those two output signals also reverses itself cyclically as the tone wheel rotates, and a phase reversal detector detects that reversal and uses the event to provide timing reference pulses for a final determination of speed.

Abstract: A silver base electrical contact material is described which contains a dispersion of particles consisting of cadmium oxide and nickel. The nickel particles are surrounded by a continuous adherent coating of nickel oxide which eliminates the detrimental reaction which would otherwise occur between nickel and cadmium oxide. The invention contact materials have improved lives and are fabricated by any one of several different powder metallurgy techniques.

Abstract: An integrated electronic control arrangement is disclosed in the illustrative environment of a gas-fired furnace. The control incororates a self-test feature which shuts down the furnace and displays a diagnostic fault code in the event of any one of a number of possible sensed faults. Self-testing occurs automatically before an attempt at ignition and during furnace operation. The self-test may also be initiated manually at any time the furnace is not operating. The control accepts digital information on daily temperature setback, weekend temperature setback and vacation setback in any one of several preset schedules and preset setback increments. The control has a multipurpose display for selectively showing component indicative failure codes, temperature setback schedules, time of day, and day of the week.

Abstract: A fail safe drive circuit for enabling the relay which in turn opens the valve for supplying gas to a burner is disclosed and includes a pair of field effect transistors both of which must be operating properly to enable the relay. One transistor receives an enabling input from a rectifier circuit and will be enabled only if the alternating input signal is of sufficient magnitude and repetition rate. The other transistor is turned on and off by the alternating input signal and the gas valve will be turned on only when each of the transistors is operating in its intended mode. The circuit thus discriminates against false enabling signals such as a direct current signal, line voltage signal, a non-repetitive alternating current signal, or other spurious signal.

Abstract: An improved coil end face insulator and the application technique therefor serve to accurately and cost-effectively insulate the end windings of an electrical coil from the transverse arm of a ferromagnetic core spaced closely thereto. The insulator is of annular, one-piece construction, and comprises adhesively-backed tape. The insulators are dispensed in a convenient manner for rapid and accurate application to the respective end faces of coils respectively positioned on a mandrel or fixture.

Abstract: A method is described for providing electrically resistive elements for mounting in an electrical resistor device for engagement with a relatively movable contact member, as in a potentiometer. A pair of termination openings are formed through a substrate of insulating material such as plastic film. A release liner is applied to the undersurface of the substrate to cover the openings. An electrically conductive medium is applied in fluid (paste) form to the top surface of the substrate and is caused to fill the termination openings, as by applying pressure. The conductive medium is solidified and the release liner is removed. A resistive medium for ultimate engagement with the movable contact is applied to the top surface of the substrate in engagement with the termination openings. The resistive track is shaped as desired, either linear or an annular segment, preferably as part of final shaping steps which also remove the resistive element from a continuous strip of the substrate material.

Abstract: An integrated electronic control arrangement is disclosed in the illustrative environment of burner such as in a gas-fired furnace. The control incorporates a self-test feature which shuts down the furnace in the event of any one of a number of possible sensed faults. Self-testing occurs automatically before an attempt at ignition and during furnace operation. Proper functioning of the sensor which senses for induced air flow through the burner combustion chamber is tested prior to enabling a fan which causes that induced air flow. Air flow is confirmed by sending to and receiving back from the sensor a sequence of pulses. Should air flow not be sensed during a combustion period, combustion is terminated. A flame sensor is provided for determining the presence of a flame in the combustion chamber. During times when a flame should be present, pulse sequences are sent to and received back from the flame sensor to confirm that a flame is present.

Abstract: An integrated electroluminescent display (DCEL), in which the DCEL (11) is integrted into the substrate board (10), such as, for example, a printed circuit board, which carries associated electronic components (12), such as, for example, those which would make up a control circuit, the DCEL displaying pertiment information for the control circuit. The bottom electrode (13) for the DCEL can be copper foil, which is etched at the same time as the rest of the foil pattern (13A) used to electrically interconnect the control components (12) of the overall control circuit during the making of the printed circuit board. Thereafter, the phosphor layer (14) is printed onto the associated copper foil segments, and, finally, a glass (15), which has on its inner surface an appropriate pattern of tin oxide (16), is placed on top of the phosphor depositions.

Abstract: A silver base electrical contact material is described which contains a dispersion of particles consisting of cadmium oxide and nickel. The nickel particles are surrounded by a continuous adherent coating of nickel oxide which eliminates the detrimental reaction which would otherwise occur between nickel and cadmium oxide. The invention contact materials have improved lives and are fabricated by any one of several different powder metallurgy techniques.

Abstract: A fail safe control circuit for supplying gas to a burner is disclosed and includes a plurality of timers, two of which set upper and lower bounds on a window or acceptable time interval during which a third timer must issue a control signal for that signal to be valid. The timers are operated from at least two different sources of timing signals so that a failure of either source of timing signals as well as a malfunction of any one of the three timers will result in an invalid control signal and the control will lock out to preclude burner operation.

Abstract: A fuel level sensor 16 comprises a vertical member 20 and float 22 wherein said vertical member 20 comprises a steel substrate 26 encased in porcelain 28 with a thick film cermet resistive track 34 deposited thereon. A nickel deposit 36 at the bottom portion of the vertical member 20 facilitates electrical continuity between the substrate 26 and the resistive track 34 such that the substrate acts as a buried conductor enabling proportionality between magnitude of resistance and liquid level while diminishing the likelihood of conductor erosion and float interference.